Comprehensive compositional analysis of liquid organic product prepared by industrialized hydrothermal cracking of biomass waste and its potential application as fertilizer

Abstract

Hydrothermal cracking involves the conversion of organic waste into efficient fertilizer through hydrolysis at temperatures ranging from 180 to 220 °C and pressures of 1.5 to 2.45 MPa, which offers significant advantages in shortening the production cycle, enhancing efficiency, and decomposing antibiotics. As a result, it holds immense practical value for promoting organic fertilizer manufacturing processes globally. The products derived from hydrothermal cracking can be categorized into solid and liquid components. Extensive research has focused on the composition and use of solids, while studies on liquids have mainly examined basic characteristics. The study aimed to comprehensively analyze the components in liquid products prepared through hydrothermal cracking and evaluate their suitability as liquid fertilizers. Specifically, we employed rigorous analytical techniques to accurately identify and quantify medium and trace elements, organic acids, amino acids, and plant growth regulators. Furthermore, we carried out a planting experiment to assess the yield and soil changes following the application of liquid products in maize cultivation. The experimental data revealed that the liquid product contained abundant medium and trace elements, along with 6.22 g/L free amino acids and 9.22 g/L organic acids. It is noteworthy that this liquid product contained 1.22 × 105 pg/ml ABA, 6.26 × 103 pg/ml IAA, 1.07 × 102 pg/ml IBA, and 3.60 × 10−2 pg/ml GA3. The utilization of this liquid product has the potential to enhance the disease resistance of maize crops and promote the accumulation of nitrate nitrogen in the soil. By understanding the composition of liquid products via hydrothermal cracking, valuable insights can be gained into their potential benefits for agricultural and ecological applications.